1. Field of the Invention
The present invention relates to a method of transferring a device, and in particular, to a method of transferring a device from a first substrate onto a second substrate by a laser ablation technique.
2. Description of the Related Art
As a method of selectively and accurately transferring part of a group of devices arranged on a first substrate onto a second substrate, there is an attempt for application of a laser ablation technique. Device transfer using a laser ablation technique is carried out as follows. First, the first substrate and the second substrate are arranged such that the device arrangement surface of the first substrate and the adhesive layer forming surface of the second substrate face each other. In this state, a laser beam is irradiated only onto a position corresponding to a device to be transferred from the first substrate side. Thus, a release layer provided between the first substrate and the device is instantaneously evaporated (ablated) and gasified, and the device is released from the first substrate, and adhered and fixed to an adhesive layer on the second substrate.
A method is also suggested in which, when the laser beam is irradiated, a first substrate and a second substrate are arranged to be spaced from and opposite each other. Thus, there are no problems due to uneven pressure imposed on the two substrates and no problems regarding alignment. In addition, there is no case where an adhesive is stuck to an excess portion or the two substrates are not completely separated from each other after transfer. Furthermore, according to this technique, the surface of the device onto which the laser beam is irradiated is processed in advance, such that the application direction of pressure of gas caused by laser irradiation is regulated and the device scattering direction is controlled (see JP-A-2002-314053 (paragraphs 0010 and 0020)).